Effectiveness of an intervention to optimise the use of mirabegron for overactive bladder: a quasi experimental study in primary care

Background Overactive bladder is a composite of lower urinary tract storage symptoms. Pharmacological treatment is widely employed despite markedly modest efficacy data, adverse effects, and costs for the health system. Aim To determine the 12-month efficacy of an intervention delivered by GPs on mirabegron revision and, if appropriate, discontinuation of treatment. Design and setting Multicentre, quasi-experimental study in Barcelona (Catalonia), Spain. Method Two groups composed of 17 intervention and 34 control practices were formed. The follow-up period was 12 months, from 1 January to 31 December 2017. A structured intervention was designed consisting of initiatives with GPs and urology/gynaecology specialists. The primary outcome was mirabegron use at 12 months. Results Of the 1932 patients, a significant discontinuation in treatment was observed at 12 months' follow-up in the intervention group (IG) (n = 433 out of 762, 56.8%), in contrast with the control one (CG) (n = 484 out of 1170, 41.4%) (P<0.001). There was also a reduced incorporation of new treatments in the IG (n = 214 out of 762, 28.1%) compared with the CG (n = 595 out of 1170, 50.9%) (P<0.001). In relation to patients with treatment at the beginning and end of the period, there was a decrease of 219 (28.7%) patients in the IG and an increase of 111 (9.5%) in the CG (P<0.001). Conclusion The structured intervention showed optimisation in the use of mirabegron. When considering discontinuation it is necessary to provide clear data on the benefits and/or risks for patients and their caregivers, as such information is a precondition for shared decision making.